[Help - Error] blocky screen

[Hetfield]

whenever i turn my character(in-game) or move to aim, screen goes kinda blocky, like boop boop boop boop, cant explain lol but its like playing minecraft on a potato.
happens from time to time, sometimes it doesnt happen at all but sometimes it stays that way for hours and gets fixed out of nowhere.
there's no way to f11 it because, i believe, it's something related to my computer. either way i'd like to find a solution. i do not run any other programs while playing, except for firefox and SOMETIMES skype.
normal settings, stable fps(75 ~ 110), windowed mode, 800x600, full config.xml here.
if my computer specs are needed, let me know.

[Amers]

It has to be your monitor, maybe you have a really old one.

[«Benjamin»]

Do you use windows 10?

[Hetfield]

It has to be your monitor, maybe you have a really old one.

http://www.lg.com/ar/monitores/lg-W1943TE-lcd

Do you use windows 10?

nope, w7 professional

[«Benjamin»]

Remove your monitor cables for 10 mins. and then reopen PC.

[Hetfield]

Remove your monitor cables for 10 mins. and then reopen PC.

already done not so long ago and it didn't work. also once tried w both fg and other server running at the same time. fg had this problem, other one didnt.

[«Benjamin»]

I'd think you have to change your monitor cables.

till you do that, I will look what else I can do to solve your problem.

[Legancy]

Recently updated your videocard drivers?
Which videocard are you using?

[Hetfield]

I'd think you have to change your monitor cables.

till you do that, I will look what else I can do to solve your problem.

i srsly doubt its my monitor <.<

Recently updated your videocard drivers?
Which videocard are you using?

i believe i did, i'm not sure lol

[Zoro]

Not sure if the following tips could be of any help.
1.Limit fps to 250 or 333
2.Open Task manager and close unwanted programs(sometimes you dont have programs open, but they still open )

maybe try lower resolution, archetype, disable extra laggy functions